add email sender and send email with password

cmd/evening_detective_server/main.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	_ "embed"
 	"evening_detective_server/internal/app"
+	"evening_detective_server/internal/modules/email_sender"
 	"evening_detective_server/internal/modules/password_generator"
 	"evening_detective_server/internal/repos/users_repo"
 	"evening_detective_server/internal/services/users_service"
@@ -43,7 +44,12 @@ func main() {
 
 	usersRepo := users_repo.NewUserRepo(dbpool)
 	passwordGenerator := password_generator.NewGenerator(8)
-	usersService := users_service.NewUsersService(usersRepo, passwordGenerator)
+	smtpHost := os.Getenv("SMTP_HOST")
+	smtpPort := os.Getenv("SMTP_PORT")
+	smtpUser := os.Getenv("SMTP_USER")
+	smtpPassword := os.Getenv("SMTP_PASSWORD")
+	emailSender := email_sender.NewSender(smtpHost, smtpPort, smtpUser, smtpPassword)
+	usersService := users_service.NewUsersService(usersRepo, passwordGenerator, emailSender)
 
 	// Create a listener on TCP port
 	lis, err := net.Listen("tcp", ":8080")

internal/modules/email_sender/interface.go

@@ -0,0 +1,13 @@
+package email_sender
+
+import "context"
+
+type Message struct {
+	To      string
+	Subject string
+	Body    string
+}
+
+type IEmailSender interface {
+	Send(ctx context.Context, message Message) error
+}

internal/modules/email_sender/sender.go

@@ -0,0 +1,94 @@
+package email_sender
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"net/smtp"
+)
+
+type sender struct {
+	smtpHost     string
+	smtpPort     string
+	smtpUser     string
+	smtpPassword string
+}
+
+func NewSender(
+	smtpHost string,
+	smtpPort string,
+	smtpUser string,
+	smtpPassword string,
+) IEmailSender {
+	return &sender{
+		smtpHost:     smtpHost,
+		smtpPort:     smtpPort,
+		smtpUser:     smtpUser,
+		smtpPassword: smtpPassword,
+	}
+}
+
+func (s *sender) Send(_ context.Context, message Message) error {
+	emailMessage := []byte(fmt.Sprintf(
+		"To: %s\r\n"+
+			"Subject: %s\r\n"+
+			"MIME-Version: 1.0\r\n"+
+			"Content-Type: text/plain; charset=utf-8\r\n"+
+			"\r\n"+
+			"%s\r\n",
+		message.To,
+		message.Subject,
+		message.Body,
+	))
+
+	// Настраиваем TLS
+	tlsConfig := &tls.Config{
+		ServerName: s.smtpHost,
+	}
+
+	// Подключаемся к серверу
+	conn, err := tls.Dial("tcp", s.smtpHost+":"+s.smtpPort, tlsConfig)
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	// Создаем SMTP клиент
+	client, err := smtp.NewClient(conn, s.smtpHost)
+	if err != nil {
+		return err
+	}
+	defer client.Quit()
+
+	// Аутентификация
+	auth := smtp.PlainAuth("", s.smtpUser, s.smtpPassword, s.smtpHost)
+	if err = client.Auth(auth); err != nil {
+		return err
+	}
+
+	// Указываем отправителя
+	if err = client.Mail(s.smtpUser); err != nil {
+		return err
+	}
+
+	// Указываем получателя
+	if err = client.Rcpt(message.To); err != nil {
+		return err
+	}
+
+	// Отправляем данные письма
+	w, err := client.Data()
+	if err != nil {
+		return err
+	}
+	_, err = w.Write(emailMessage)
+	if err != nil {
+		return err
+	}
+	err = w.Close()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

internal/services/users_service/service.go

@@ -2,8 +2,10 @@ package users_service
 
 import (
 	"context"
+	"evening_detective_server/internal/modules/email_sender"
 	"evening_detective_server/internal/modules/password_generator"
 	"evening_detective_server/internal/repos/users_repo"
+	"fmt"
 
 	"golang.org/x/crypto/bcrypt"
 )
@@ -11,15 +13,18 @@ import (
 type UsersService struct {
 	usersRepo         *users_repo.UsersRepo
 	passwordGenerator password_generator.IPasswordGenerator
+	emailSender       email_sender.IEmailSender
 }
 
 func NewUsersService(
 	usersRepo *users_repo.UsersRepo,
 	passwordGenerator password_generator.IPasswordGenerator,
+	emailSender email_sender.IEmailSender,
 ) *UsersService {
 	return &UsersService{
 		usersRepo:         usersRepo,
 		passwordGenerator: passwordGenerator,
+		emailSender:       emailSender,
 	}
 }
 
@@ -43,5 +48,15 @@ func (s *UsersService) AddUser(
 		string(hashedPassword),
 		"user",
 	)
+	if err != nil {
+		return err
+	}
+
+	err = s.emailSender.Send(ctx, email_sender.Message{
+		To:      email,
+		Subject: "Приветствую тебя, детектив!",
+		Body:    fmt.Sprintf("Вот твой пароль для входа в систему: %s", password),
+	})
+
 	return err
 }